1. Field of the Invention
The present invention generally relates to computer-aided design, and particularly relates to a scenario generating method, a scenario generating program, and a scenario generating apparatus that generate a scenario for checking the functions of an LSI.
2. Description of the Related Art
Due to the improvement of the integration density of LSI (large scale integrated) circuits, it has become possible to implement a complex system on a single chip as an SOC (System on Chip). In the case of an LSI circuit such as an SOC having large-scale and complex functions, the task to check such functions is cumbersome as it requires a significant amount of time and labor.
In order to check the functions of an LSI, there is a need to exhaustively check all the functions of the LSI specified in its specification sheet. Such a specification sheet describes all the operations of an LSI to be designed, and a series of such operations constitute a scenario. The term “operation” refers to a single action that is obtained by breaking down the specifications. In an example of a recorder LSI, for example, each action such as “recording”, “pausing during the recording operation”, and “playing” corresponds to a single operation. Further, the term “scenario” refers to a series of operations that makes sense for the purpose of testing the functions of the LSI. The scenario may be regarded as a test program for checking the LSI. In the example of a recorder LSI, a series of actions such as “power-on->recording operation->pause operation” is a scenario for checking a basic recording function of the recorder LSI.
A meaningless arrangement of operations does not make sense as a scenario. In the example of a recorder LSI, a sequence of operations such as “power-off->recording operation” does not make sence. Accordingly, there is a need to extract, from a specification sheet, a scenario as a series of operations with proper meaning for the purpose of testing the function of the LSI. It should be noted that a specification sheet does not describe all the scenarios that should be checked, but describes only part of such scenarios. In a specification sheet of a recorder LSI, for example, a scenario stating, “perform a recording operation for the purpose of recording, and, then, perform a pause operation for the purpose of temporarily suspending the recording,” may be described, but a series of operations comprised of “recording operation”->“pause operation”->“pause resetting operation (resuming the recording)” may not be necessarily described as a single, complete scenario.
Accordingly, in order to exhaustively check all the functions of the LSI, there is a need to extract not only the scenarios expressly described in the specification sheet but also the scenarios that are not expressly described in the specification sheet but can be composed by combining individual operations described in the specification sheet. Namely, not only the scenarios expressly described in the specification sheet need to be extracted, but also scenarios that are not directly described in the specification sheet need to be generated.
Specification sheets are written in natural languages such as Japanese, English, etc. Accordingly, it is desired to devise a method that can convert the contents of a specification sheet into a predetermined notation treatable by a computer, and that can then generate all the scenarios systematically from such a notation.
[Non Patent Document 1]
Ryosuke Oishi, Qiang Zhu, Tsuneo Nakata, Masataka Mine, Ken'ichiro Kuroki, Yoichi Endo, Takashi Hasegawa, “A methodology for high-level verification with UML,” 2004 Proceedings of DA symposium, July, 2004
[Non Patent Document 2]
Q. Zhu, R. Oishi, T. Hasegawa, T. Nakata, “System-On-Chip Validation using UML and CML,” CODES+ISSS 2004, September, 2004
[Non Patent Document 3]
Q. Zhu, R. Oishi, T. Hasegawa, T. Nakata, “System-On-Chip Validation using UML and CML,” CODES+ISSS 2004, September, 2004
Accordingly, there is a need for a method that can systematically generate all the scenarios from a specification sheet in order to exhaustively check the functions of the LSI.